Shoreline Management Act jurisdiction

Where does the state Shoreline Management Act apply?

  • All marine waters along the Pacific Ocean and Puget Sound
  • Streams and rivers with an annual mean flow of more than 20 cubic feet per second
  • Lakes greater than 20 acres in size
  • Shorelands adjacent to these water bodies (typically within 200 feet of the water body but there are exceptions)
  • Associated wetlands

Under state law, specific larger water bodies are shorelines of statewide significance.

Naturally occurring and human-engineered alterations in our shoreline area can result in modifications to shoreline jurisdiction boundaries when an action changes the "ordinary high water mark" or other physical characteristics that determine jurisdiction of the state Shoreline Management Act. Examples of such alterations include:

  • Permitted, human-engineered changes such as filling and dredging
  • Flood-control projects
  • Natural changes due to landslides, flooding, channel alterations, and river course changes

Shoreline master programs officially delineate shoreline jurisdiction

When we approve a locally tailored, updated comprehensive shoreline master program from a city or county, our decision means the water bodies covered under state law have been delineated. Each shoreline program contains maps and legal descriptions of these delineated streams and rivers, lakes, shorelines and wetlands. 

You may request a copy of the current shoreline program from your local planning office. You may also request a copy from Jackie Chandler, shoreline administrator:, 360-522-3927.

Other key shoreline jurisdiction terms and concepts: